A huge fire at a music festival in Spain forced the evacuation of over 20,000 concertgoers and incinerated the event's stage in Barcelona, the regional government said Sunday.

The fire Saturday night consumed the large outdoor stage at the ``Tomorrowland'' electronic music festival held at Barcelona's Parc de Can Zam. Twelve firefighting units needed around an hour to extinguish the flames just before midnight.

Firefighters said they were investigating the cause. The ``Tomorrowland'' website published a statement saying the ``stage caught fire due to a technical malfunction.''

Barcelona firefighters said there were no serious injuries during the evacuation but the event's private security treated 20 people for minor injuries or anxiety.

Video images show the fire starting at the top of a tall temporary structure erected on the stage where a large screen showed a performer signing. The towering flames quickly spread until they engulfed the entire stage.

In a statement, regional authorities said the fire ``completely destroyed the stage'' and that its charred remains ``run the risk of collapsing.''

The festival in Barcelona was one of several offshoots of a main ``Tomorrowland'' festival in Belgium. Organizers said the Barcelona event was canceled following the fire. (AP)